This application claims priority to Great Britain application No. 9619173.9 filed Sep. 13, 1996 and Great Britain application No. 9707019.7 filed April 07, 1997.
The present invention relates to image processing, and in particular to the conversion of film images to video images and the colour correction of such images.
Currently, there exist specialist machines (xe2x80x9ctelecinexe2x80x9d machines) to scan cinema style motion picture film, and derive electrical signals for recording onto videotape or broadcasting as television pictures. One such example of this is the xe2x80x98URSAxe2x80x99 telecine, manufactured by Rank Cintel Ltd. in Ware, England.
It is known to have a xe2x80x98gradingxe2x80x99 mode for these telecines, where scenes are studied, and a colour correction data set is visually determined for individual scenes. The process of building up a series of colour correction values for a number of scenes, which is then used in a real time xe2x80x98transferxe2x80x99 mode to effect the colour correction is taught in U.S. Pat. No. 4,096,523. An example of a telecine controller and programmer embodying such a process is the xe2x80x98POGLExe2x80x99 produced by Pandora International Ltd.
External visual picture still-store devices, such as the Rank Cintel xe2x80x98Matchboxxe2x80x99 are also known, and these can be used in conjunction with a telecine and programmer to view images from individual scenes. The use of such still stores, in conjunction with a controller, is taught in U.S. Pat. No. 4,763,186. From this document it is known to display a xe2x80x9cstoryboardxe2x80x9d of the overall film work to be transferred by using a TV monitor screen as a xe2x80x98polyphotoxe2x80x99 displaying an array of, for example, 5 by 4 pictures (20 pictures in all) corresponding to individual scenes of the cinematographic work. Such a system provides the user with a xe2x80x98linkxe2x80x99 between miniature displays of stored still frames of picture relating to each scene for xe2x80x98cueingxe2x80x99 the telecine to the associated scene, and recalling the associated correction data.
It is also known to store a graded transfer of a film on a magnetic or optical hard-disk or in a RAM system. One such video disk system is designed and manufactured by Abekas Ltd, of the USA and an example of a RAM (Random Access Memory) system is the xe2x80x98SSVRxe2x80x99 (Solid State Video Recorder) manufactured by Questech Ltd of Wokingham, England.
In this case, if the controller is instructed to display a given scene, it can instantly replay that scene from the hard disk or RAM store. This saves waiting for the telecine to rewind, and also offers the advantage of putting less xe2x80x98wear and tearxe2x80x99 on the valuable camera original film.
Current telecine controllers present the user with a list of xe2x80x98scene changexe2x80x99 data involving alphanumeric data containing information about the frame number associated with the start and end of that scene, together with information contained in an operator defined comment field, such as xe2x80x98Girl in red dressxe2x80x99 or similar.
Visual references can also be provided separately in the form of one still frame per scene, which can be displayed on a still store of the xe2x80x98Matchboxxe2x80x99 type.
The alphanumeric data relating to scene changes is presented to the user, in known systems, on the VDU of a computer terminal. For example in the POGLE controller/programmer, produced by Pandora International Ltd. an industry standard Silicon Graphics xe2x80x9cINDYxe2x80x9d terminal has been used as the interface, although this terminal is longer available.
According to the present invention, a method of processing digital image data is provided, wherein cinematographic film is scanned to produce digital image data corresponding to the image(s) stored on the film; the digital image data is stored in data storage means; adjustments are made to the digital image data by a processor at the request of an operator; when an adjustment is requested by an operator the adjustment is compared to predetermined criteria; and a signal is generated if the adjustment requires the digital image data to be re-scanned from the film.